Feeding world, protecting planet a huge challenge

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Combining new data gathered from satellite imagery and crop records around the world with new computer models of global agricultural systems and their environmental impacts, the team developed a plan for doubling the world’s food production while reducing environmental impacts of agriculture.

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Can we feed the more than 9 billion people anticipated to live on this planet in 2050 without destroying Earth’s life support systems?

In an article slated to appear as the cover story in the Oct. 20 print issue of Nature, a team of researchers from the U.S., Canada, Sweden and Germany conclude we can — if we successfully pursue sustainable food production on five key fronts: halting farmland expansion in the tropics, closing yield gaps on underperforming lands, using agricultural inputs more strategically, shifting diets and reducing food waste.

An online version of the article will be available starting today at www.nature.com.

“For the first time, we have shown it is possible to both feed a hungry world and protect a threatened planet,” said lead author Jonathan Foley, head of the University of Minnesota’s Institute on the Environment. “It will take serious work. But we can do it.”

Scientists from the University of Minnesota, University of Wisconsin, McGill University, UC Santa Barbara, Arizona State University, Stockholm Resilience Centre at Stockholm University, Stockholm Environment Institute and the University of Bonn have been working together for two years to find an answer to what could be the most compelling question facing humanity today.

Combining new data gathered from satellite imagery and crop records around the world with new computer models of global agricultural systems and their environmental impacts, the team developed a plan for doubling the world’s food production while reducing environmental impacts of agriculture.

The research was a response to what Foley calls “a daunting triple threat.” “First, a billion people currently lack adequate access to food, not only creating hunger but also setting the stage for worldwide instability.

Second, agriculture, the single-most important thing we do to benefit humanity, is also is the single biggest threat to the global environment – including the land, water and climate that make Earth habitable.

Third, with 2 to 3 billion more people expected in coming decades, and increasing consumption of meat and biofuels, food demand will be far greater in 2050 than it is today,” Foley said. “Given that we’re not even able to meet current needs sustainably, how will we feed the anticipated more than 9 billion of us without destroying the planet?”

Using new satellite and ground-based observations, the team documented changes in agricultural lands and their yields over the past 40 years. Currently, farm and ranch lands cover nearly 40 percent of Earth’s land area — the largest use of land on the planet.

Though modern agriculture has boosted crop yields, increases between 1985 and 2005 were less than half what is commonly reported and are slowing. And because one-third of crops are used for livestock feed, biofuels and other non-food products, the number of hunger-abating calories produced per cultivated acre is far lower than it could be — even in fields with high-yielding, but animal-feeding, crops.

This comes with a hefty environmental price, the researchers say. Humans have already cleared 70 percent of all grasslands, half of all savannas, 45 percent of temperate deciduous forests and 27 percent of tropical forests.

In addition, intensification of agriculture — changes in irrigation, fertilizer use and other practices aimed at boosting per-acre yield — has increased water pollution, local water shortages and energy use.

Strikingly, agricultural activities such as clearing land, growing rice, raising cattle and overusing fertilizers make up 35 percent of the single largest contributor of greenhouse gases to the atmosphere.